I-380 highlighted in red | ||||
Route information | ||||
Auxiliary route of I-80 | ||||
Maintained by Iowa DOT | ||||
Length | 72.969 mi[1] (117.432 km) | |||
Existed | c. September 19, 1973[2]–present | |||
History | Under construction 1973–1985 | |||
NHS | Entire route | |||
Major junctions | ||||
South end | ![]() ![]() ![]() ![]() | |||
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North end | ![]() | |||
Location | ||||
Country | United States | |||
State | Iowa | |||
Counties | ||||
Highway system | ||||
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Interstate 380 (I-380) is a 73-mile (117 km) auxiliary Interstate Highway in eastern Iowa. The route extends from I-80 near Coralville to Waterloo. I-380 connects the cities of Cedar Rapids and Waterloo, the state's second- and sixth-largest cities, respectively, to the Interstate Highway System. Except for its last 1.5 miles (2.4 km) north of U.S. Highway 20 (US 20), I-380 runs concurrently with Iowa Highway 27 (Iowa 27), which represents Iowa's portion of the 560-mile (900 km) Avenue of the Saints highway connecting Saint Louis, Missouri, with Saint Paul, Minnesota.
Construction of I-380 took 12 years to complete, ending in 1985. After the Interstate opened, US 218 was moved onto the new freeway south of Cedar Rapids. In the 1990s, the I-380 corridor was selected as part of the Avenue of the Saints corridor, which Iowa designated as Iowa 27 in 2001. I-380 has been affected by two major floods, the Great Flood of 1993 and the Iowa flood of 2008, both of which closed the road at the Iowa River for two weeks.